What was the case yesterday doesn’t have to be the case today. Full wells and groundwater reservoirs are not so obvious in some localities anymore. The Czech Republic is called the roof of Europe for a reason: the water supplies in rivers, ponds, and especially the underground are being replenished only from the rainfall which is not enough. No river flows into our country, on the contrary, all the water flows out to our neighbors. As a result of the climate change, we have been increasingly experiencing periods of drought, especially in the last 5 years. According to experts, drought, like the other extreme, flood, is a phenomenon that our society needs to count with, as it will affect us more and more often. The increasing difficulty with obtaining of the water results in its increasing price. In 1990 a cubic meter of water cost CZK 80, in 2019 it was almost CZK 90. How to prepare for the drought and what can each of us do?
Water supply, i.e. production of drinking water, has a very long tradition in our country. Few people realize that by connecting our apartments and houses to the public water network, we have gained a service that brings access to an almost unlimited amount of water of a very high quality. This luxury has been achieved only few decades ago and, in addition to comfort, made it possible to improve the hygienic and health conditions. We still use the highest quality water not only for drinking and personal hygiene, but also for convenient waste removal in the form of flushing toilets, filling swimming pools, but also irrigating greenery or cleaning the streets. However, the need to maintain such a high standard and to satisfy an increasing demand also has a negative consequence, namely an increase in price.
According to statistics, Prague households consume the highest amount water in the whole Czech Republic. According to the Prague Waterworks and Sewerage Company, in recent years it has been above 100 liters per person per day. In contrast, an average person in the Zlín Region consumes 30 liters less per capita. About 40% of the water is consumed for personal hygiene, 25% for flushing toilets, 16% for cleaning, 10% for cooking, drinking and washing dishes, 5% for watering and 4% take other activities, including filling of swimming pools.
Technical advances help to reduce water consumption by energy-saving faucets and shower heads, two-button flushing, dishwashers, energy-saving washing machines, etc. Another major saving can be achieved by answering the question – do we really need flushing, i.e. the removal of waste from our household, with high-quality drinking water? Skanska Reality is convinced that we don’t. They are looking for flushing alternatives to fully replace drinking water. The gray water system, which has been operating in the Botanica K apartment building for more than a year, consists of capturing water from sinks, showers and bathtubs, treating and reusing it for flushing toilets. The building and each of the inhabitants will thus save a quarter of the financial costs than the inhabitants of an ordinary building. Another alternative to save drinking water is flushing with water from a well, which is planned for the last stage of the Karlín project Port Karolína D, which is meeting strict criteria for the building's impact on the environment according to international BREEAM certification.
In addition to the mentioned installations of more economical technologies in the household, drinking water can also be saved by capturing and subsequently using rainwater. This can be used, for example, for irrigating greenery, i.e. the garden or public space in the area. To replenish groundwater supplies, we need our only source – the rainwater to be managed as best as possible and to slow down its outflow. We can achieve this by building various types of polders and storage retention tanks, which do not allow water to drain away during rainfall, but also help with its infiltration into the soil.